Fast semistochastic heat-bath configuration interaction
Abstract
This paper presents in detail our fast semistochastic heat-bath configuration interaction (SHCI) method for solving the many-body Schrödinger equation. We identify and eliminate computational bottlenecks in both the variational and perturbative steps of the SHCI algorithm. We also describe the parallelization and the key data structures in our implementation, such as the distributed hash table. The improved SHCI algorithm enables us to include in our variational wavefunction two orders of magnitude more determinants than has been reported previously with other selected configuration interaction methods. We use our algorithm to calculate an accurate benchmark energy for the chromium dimer with the X2C relativistic Hamiltonian in the cc-pVDZ-DK basis, correlating 28 electrons in 76 spatial orbitals. Our largest calculation uses two billion Slater determinants in the variational space and semistochastically includes perturbative contributions from at least trillions of additional determinants with better than 10−5 Ha statistical uncertainty.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 06, 2018
- Source ID
- 10.1063/1.5055390
Entities
People
- Adam A. Holmes
- Cyrus Umrigar
- Junhao Li
- Matthew Otten
- Sandeep Sharma
Organizations
- Air Force Office of Scientific Research
- Cornell University
- National Science Foundation
- United States Department of Energy
- University of Colorado Boulder